The disclosure relates generally to dynamic control of tolerances in a machine, and more particularly, to tolerance control in a spray nozzle, such as may be used in gas turbine systems and other machines.
A variety of machinery includes spray nozzles and other components that require precise internal dimensions to operate effectively. These same components can be subject to wear and deformation during operation that may alter one or more critical dimensions of the component. For example, a spray nozzle may be subject to mechanical and electrochemical erosion, causing the diameter of the aperture controlling fluid flow to increase and thereby decrease fluid pressure in the system and undermine the desired fluid velocity and dispersion. In some cases, decreased performance requires that the eroded spray nozzles be removed and replaced.
Some gas turbines may include a wet compression system to improve turbine operation power output in high temperatures (ambient air over about 60 degrees Fahrenheit). Wet compression systems may include a water injection rack mounting an array of spray nozzles, specifically small capacity hydraulic atomizers, connected to one or more valve-controlled water paths for precisely controlling location, timing, and pressure of water injected into the gas turbine for cooling. Such wet compression systems may create finely atomized water drops (1-50 micron diameter) injected into an air inlet duct through spray nozzle apertures with critical dimensions of less than several hundred microns. Droplet size is important to control the timing and distribution of evaporative cooling of water droplets entering the compressor stages. Changes of critical internal dimensions in the spray nozzle over time due to erosion may cause a greater variation in droplet sizes and/or increases in mean droplet size. These changes may have adverse impact on gas turbine performance and wear, including airfoil damage or degradation.